You know something that’s happened fairly recently in the automotive world that has been largely overlooked? Three cylinder engines have gotten more mainstream than ever before – well, at least in America, in some times and places, like Eastern Europe between the 1950s and 1990s they were the most common type of engine – and they’re now in bigger cars than ever before. In fact, I think when it comes to mass-produced three-cylinder passenger cars, we now have the biggest one on the market ever. Do you know what car that is? I think I do!
Three-cylinder engines have never been as popular as four-bangers, even at small displacements, because they’re inherently unbalanced in the “rocking couple” way– that is the cylinders on either side of the middle one don’t have symmetrical velocities. There may be other reasons, but the need for balance shafts and that sort of engineering definitely is a factor.
Still, the three did find use, especially in two-stroke form, as pioneered by Germany’s DKW, with variations of their three-cylinder two-stroke ending up in countless Wartburgs, Saabs, Barkas vans and trucks, and some motorcycles, and more. For small cars, threes have always had the advantage of economy, something perhaps best known in America thanks to the Geo Metro (which is actually a Suzuki Cultus), the hypermiler’s dream car.
But now we’re in a sort of three-cylinder renaissance, with lots of major automakers having some kind of new, advanced three, and with these engines ending up in cars far different than the usual Eastern Bloc socialism-wagon or some little Japanese econobox. Now they’re appearing in SUVs and even supercars.
So, what’s the biggest three-banger out there? To help figure that out, I made this chart:
This, of course, does not cover all the three-bangers out there, but tries to give a decent representative sampling. Small ones are plentiful, and vary pretty dramatically, from little sports cars like the Saab Sonett to Japanese Kei cars to the ubiquitous-in-India Maruti-Suzuki, to the little Smarts, to modern BMW-made Minis.
The middle section has all those wonderful DKWs that live on through Audi, at least in the logo, along with the Eastern Bloc’s most Volvo-ish car, the Wartburg, and then those Saabs before the company switched to the four-stroke V4 from the Ford Taunus.
The Big Boys are the most recent ones; there’s the hybrid BMW i8 which was one of the first near-supercars to give a triple-piston engine a go, when paired with some electric motors, a formula that was taken and absolutely run with by Koenigsegg for their Gemera. That three-cylinder engine, called the Tiny Friendly Giant, displaces two liters, has twin turbos, cam-less valves, and somehow makes 600 horsepower!
Here, let’s geek out about that for a moment:
Damn!
Okay, back to sizes of three-cylinder cars, though. Both the BMW i8 and Gemera are long and wide and low, and if you multiply their lengths, widths, and heights to get the volume of space they take up, they both come to a volume of around 700,000 cubic inches. That’s a big block of space, but there are bigger three-bangers.
Take the Buick Envista, which our own Matt Hardigree reviewed back in March; that’s an SUV with a 1.2-liter three, and is 183 inches long, 72 inches wide, and 61 inches tall. That gives us an overall volume of 803,736 cubic inches! That’s a lot!
But there’s one more Big Three out there: the Ford Bronco Sport. This is the car that got me thinking about all of this from the beginning because it is a car that I suspect most of its buyers do not even realize is a three-cylinder. It just doesn’t feel like one. So how big is it?
Well, the Bronco Sport is 173 inches long, 74 inches wide, and 71 inches tall (with the roof rack); that gives us a total volume of 908,942 cubic inches, which I believe makes it the biggest three-cylinder car available now, and, I think, likely ever!
I know there are big diesel trucks that have some massive displacement three-cylinder engines, and of course those are larger, but we’re talking mass-market passenger cars here.
So, if you were wondering, my conclusion is that the Ford Bronco Sport is the biggest three-cylinder-powered mass-marker passenger car ever made!
No go forth with this newfound knowledge and win some bar bets or something!
No bigger than the Ford, but I think the most unexpected is the Alfa Romeo 33 1.8 TD.
Three cylinders of raw diesel power thanks to VM Motori – actually, this is a shorter stroke version of the same engine as fitted to David’s Chrysler Voyager (minus one cylinder). When I first saw this listed in the 1987 Auto Katalog I simply assumed it was a typographical error; it wasn’t until I got my first graphing calculator that I verified the number of cylinders from the reported bore and stroke.
You also mustn’t forget that time, when BMW thought it’d be funny to stuff a 3-cylinder into a 3 Series. The F30/31 318i. Boy howdy, did we laugh here in jolly old Europe.
My 3-cylinder, 1st gen Honda Insight, would graciously like to point out that its feelings were hurt at not being included in this article.
My understanding is that to make the 3-banger more palatable, Honda’s ECU bumps the electric motor in just the right spot in the engine’s rotation to smooth out the vibrations and make the whole car feel much more sophisticated. There have been many ecomodders – or just folks whose hybrid systems pooped out – that discovered that, while their Insights work perfectly well as strictly-ICE cars, they are far coarser without the motor providing that little anti-vibe jolt.
Ford made a bigger 3 cylinder car than the Bronco Sport. In Europe you could buy the Mondeo (US 3rd Gen Fusion) with the 1.0L EcoBoost at 125hp. I just googled and it’s 191″ long. Not as tall as the Bronco but 811,943.433 cubic inches…
Apparently not terrible, but 12 seconds 0-60mph.
https://www.topgear.com/car-reviews/ford/mondeo/10-ecoboost-titanium-5dr/first-drive
I was looking for this one. It’s possible the Bronco Sport weighs more so it may be bigger in that way, but not the largest based on size and certainly more disparate in size vs. engine displacement. And even the donor Escape with the same 1.5T I3 is 8″ longer than the Bronco Sport.
Far from the biggest, but does the inline-3 in a GR Yaris count as the most fun use of a three cylinder?
Alright so answer another related question. What is the biggest displacement three cylinder engine installed in a car ever?
The Triumph Rocket 3 has a 2458cc Inline-3.
So if someone’s converted one into a car, then it’ll be that car.
In the late-60s/early-70s Ford was building a tractor with a 2.6 liter 3-pot, but the engine is also structural; you’ll never spot someone swapping in that 600-lb lump to have all of 36 horsepower. Lots of torque though.
On this side of the Pond there are at least two bigger using your volume.
The Land Rover Discover Sport P300e is 181″ long x 75″ wide x 68″ tall which gives a cubic volume of 922428.
Then there is the Dacia Jogger. At 179″ long, 79″ wide, and 66.5″ tall it comes in at a whopping 940647 cubic inches. Even better, mine is manual and brown according the to the registration document (more of a dark metallic orange in real life).
There probably are bigger still but those were two that immediately sprang to mind.
I must insist that all vehicles mentioned have their true volume measured via the water displacement method.
You don’t need to do the water displacement method to arrive at the exact displacement. You can do it mathematically. This is how the engine displacement is taxed in some countries regardless of how much volume inside the cylinder head, recessed part of cylinder, and/or top end shape of the cylinder (flat, dome, etc).
Volume = 3.14 x (bore diameter/2) x ( bore diameter/2) x stroke
or
Cylinder Volume = bore x bore x 0.7854 x stroke
then
Engine Displacement = Cylinder Volume x Number of Cylinders
For the mathematically-inept person, here’s the online calculator.
I meant the actual irregular volume of the vehicles themselves. All the calculations are normalized to a rectangular prism, I was suggesting tongue in cheek that they all be submerged and the volume of water displaced used as the volume measurement, rather than l * w * h of the largest listed exterior measurements.
windows up or down?
Ha! I actually thought about this. It’d be quicker with the windows down but given the the glass will still occupy the same volume inside the door as out of it, it doesn’t matter too much 😉
Here’s a question about ethics. Say you’re a sales rep at the Ford Farm Equipment store and Mr. and Mrs. Emptynester take a Bronco Sport for a test ride and they’re all smiles. Do you casually mention the three banger engine, or do you keep your mouth shut and take their money? For the record, I test drove an Envista and was pleasantly surprised by its performance. I knew what it was going in but the rep wanted to make sure I knew about the engine. That was decent of him.
I mean. If someone is making a big deal out of caring about the number of cylinders, sure. But it doesn’t strike me as a sleight-of-hand at all not to mention it if it doesn’t come up. If they’re happy, it’s not very different at all from mentioning or not mentioning the aspect ratio of the tires or the final drive ratio. If they know or care to know, great! If not, it’s not unethical to let the Vehicular Appliancemobile be an appliance to the appliance-buyer.
That said, if they’re unhappy with the acceleration, NVH, some other engine-related aspect, by all means mention it.
How many Camry owners know how many cylinders their engine has?
I am just now realizing the Bronco II has a 3 cylinder in it.
I once test-drove a Focus with the 1 liter triple and a six-speed. Sixth gear was only useful going down a hill – it could not even maintain speed on level ground. Pass.
I had one as a rental. It started showing me optimistic fuel economy when I started the week, but by the end it was abysmal due to the effort I put into abusing that engine to get it to go.
Contrasted with a VW1.0, where the vw was brilliant.
I was going to say Jeep M677. But I’ll wager a guess military production runs of 300 units probably don’t count towards the theoretical goal.
It would seem to me that the weaknesses such as balance and low power could be overcome by combining two three cylinder engines with a shared crankshaft. Say, one behind the other or maybe next to each other in something like a V shape.
Just spit-balling here.
The V layout reduces the balance problem but can’t be balanced. Not unless you do it with four I3s instead of two.
Two I3s in a row are perfectly balanced. [note to DT: this is not a justification for owning two i3s]
Don’t forget about the GR Yaris and GR Corolla. That’s a fun engine that hopefully will end up in some more sporty applications from Toyota.
And it is so effing slow. You can not feel the the 181 hp nor the 190 lbft of torque in any situation and in return you get mediocre 24 mpg.
Pff 3 cylinder is over done we need more 7 cylinders
People are getting silly here so I shall suggest a three cylinder engine that might in a different universe propel a vehicle. Ladies and Gentlemen, may I introduce you to “The Sir William Prescott”
https://www.youtube.com/watch?v=OV1AZ5IAUl8
And that’s what ‘getting up a head of steam’ means, kids!
Talk about burying the lede: These are 2-stroke, 3 cylinder, 6 opposed piston 10.6 liter engines.
‘
Ford Should put a 6 speed manual behind the 1.5L I3 in the Bronco Sport, then they should put it in the Maverick and the Transit connect as well.
I somewhat irrationally love inline 3s.
I was going to say, it’s already there in Europe, but that Transit Connect never had the 1500cc I3, only the 1000cc version.
They did get the naturally aspirated 1.0L 3 cylinder which was pretty cool
If only they’d sold the dying generation of fiesta and focus st here.
I love inline 3s so much that I think I would like a car with two of them! Maybe you can mate them together side by side so it was a ][ configuration. Or maybe even V? Of course why stop there, let’s keep putting those things together…
I apparently missed that the zombified Fisker Karma (sorry, Karma Revero) had switched to using the BMW i8’s powertrain. It comes in a bit short on the volume calculation, but it’s nearly a ton heavier (approx 5400lbs), which has to put it in the running.
Ford Escape occupies roughly 884,090 cu-in and Nissan Rogue occupies 881,072 cu-in. Both are smaller than the Bronco Sport, but have longer wheelbases.
It’s kind of startling how many three cylinder powered vehicles are available today. The Rogue is the craziest to me since it’s a turbo charged, direct injected, variable compression, three cylinder engine mated to a CVT and AWD pulling a 3763 lbs crossover with a 1500 lbs towing capacity. I’d hate to own one of those outside of warranty coverage.
I came here to say Nissan Rogue, but apparently it’s just slightly smaller.
Expounding on the already-stellar powertrain reliability /s of the Talltima, Nissan decided on this path. Interesting to see how it plays out.
And in the 3 hole diesel truck division, we have Detroit Diesel 3-53 powered stepvans with over 10,000 pounds GVW. GM offered the 3-53 Detroit Diesel as a factory option and Continental Baking had the 3-53 in Ford chassis, not sure how they got there.
Bronco Sport 1.5l 3-cylinder – 29mpg highway
2023 Dodge Charger 3.6L V6 – 30mpg highway
2011 Lincoln Town Car 4.6L V8 – 24mpg highway
I don’t know, honestly doesn’t seem that impressive for a smallish, 5 passenger tall wagon with such a small engine
The Ford Focus got 40mpg with a manual and 38mpg with an automatic from the 1.0 3-cylinder (the latter number is mostly theoretical, the transmission would actually have to function to deliver any fuel economy number)
CdA values matter. Greatly.
I think it’s a good example of there’s no replacement for displacement, but not in the way most think. If you want to make the most horsepower and torque while getting the best MPG out of a gas engine an understressed naturally aspirated engine with enough displacement that 99% of the time you’re not wringing it out or barely using it’s power is what you want. You want to be in the sweet spot of chugging along while not chugging gas.
The Bronco Sport is stuck with a meh automatic and a turbocharger. A 6 speed manual would go a long way in improving IRL MPG figures.
Can’t necessarily disagree. My old ’96 Thunderbird with the 4.6 V8 could easily get 26 mpg on the highway cruising about 2000 rpm at 75 mph.
Factor in aerodynamics too, which go against the Bronco compared to the other cars in the list.
Also there’s no need for a manual (these days autos are pretty efficient), but also gearing will play a part as well.
Efficient when it comes to EPA tests, not so much irl
Now compare it to SUV’s with those engines.
I compared it to vehicles that perform the same tasks that 99.99% of Bronco Sport buyers purchase it to perform
Vehicles that actually “perform the same tasks”:
‘24 Nissan Rogue: 30mpg city / 37mpg highway
’24 Ford Escape: 42mpg city / 36mpg highway
‘24 Trailblazer: 29mpg city / 33 highway
The Bronco Sport is effectively replacing the Escape, Escape sales have been trending down ever since it was introduced and its being dropped after the 2025 model year. And the Escape became the effective replacement for the Focus, when Ford decided to drop all passenger cars, so its part of a trend toward them moving towards vehicles with worse fuel economy over time.
They’re still more efficient and more comparable than the vehicles you originally listed.
The intention was to compare a compact crossover vehicle with a tiny engine with a couple of full-size landyachts with “big” engines that are often thought of as gas hogs, as well as with a traditional compact car that they have effectively replaced.
And my intention was to point out the competing compact crossovers with a greater CdA exceed the city fuel economy of those boats by nearly double, and exceed the highway fuel economy by up to 23%.
Point is, the Bronco Sport is hilariously bad for a 1.5L anything.
Great, my point is that it doesn’t represent the whole of compact crossovers, let alone hybrids.
the trailblazer also has a 3 cylinder. and so does the escape.
2024 Bronco Sport 1.5l 3-cylinder – 25mpg city
2023 Dodge Charger 3.6L V6 – 19mpg city
2011 Lincoln Town Car 4.6L V8 – 16mpg city
This is the real difference based on use cases, though you are right, and I am amazed at how inefficient the Bronco Sport is. It’s impressively bad. The long-term average for my old 235i was 24mpg from mixed driving and I could easily do 32 or more in purely highway driving. I know which one was more fun to drive.
the bronco sport has taller truck tires and has the aerodynamics of a brick. You can’t just look at engine displacement for fuel economy weight and aerodynamics is much more important. That’s why corvette owners are able to get over 30 mpg if they can keep their foot out of it on long highway drives.
The Ford Escape has one too, and is just shy of the Bronco Sport’s size/weight I believe.
“…sports cars like the Saab Sonnet…”
Sonett, not Sonnet. It’s time for a quick review:
The one-N Sonett,
He’s a Swede.
The two-N sonnet,
Verse you read.
And I would bet
An Easter bonnet
There ain’t no
Two-N, two-T sonnett.
(Apologies to Ogden Nash.)
Also, as long as I’m being picky, the 96 used in that image is a later V4 car.
Did he invent the Rambler?
I wouldn’t say he invented the form but he certainly wrote his share of ramblers:
The one-l lama
He’s a priest.
The two-l llama
He’s a beast.
And I will bet
A silk pajama
There isn’t any
Three-l lllama.*
*The author’s attention has been called to a type of conflagration known as a three-alarmer. Pooh.
the pic is a ’68, which was the last year of the 3-cylinder option. I didn’t see the V4 badge, so I hoped
The giveaway is the taller windshield. There were a few early V4 cars made with the shorter windshield but no two-strokes made with the taller one. The one you used above is this car:
https://www.classicautomall.com/vehicles/4290/1968-saab-96-deluxe
As a point of comparison, my race car has a three-cylinder, two-stroke engine and a short windshield whereas my former tow vehicle, parked next to it, was a V4 car with a tall windshield. My other former 96 at the back was also a short-windshield two-stroke car:
https://live.staticflickr.com/6029/6098032932_9c1bcaef35_c.jpg
The tall-windshield cars also have larger rear glass:
https://live.staticflickr.com/5818/20910123461_a225c21dbd_c.jpg
It helps to know a little Swedish* (or, in this case, German works, too, because it’s the same) to get the name: “So nett!” Or, “So nice!”/”So neat!”
*Probably helps to know a little Swede, too, since a big one won’t fit.
shit. I fixed it, but look, if I didn’t screw it up, I’d not have this poem!
Thanks! I can’t take credit for the poem. It’s been circulating in the Sonett community for decades. I first saw it back when I owned this ’69 Sonett V4:
https://live.staticflickr.com/8231/8383618761_4b273123b1_c.jpg